Purpose: This study aimed at using the DGGE method to rapidly evaluate virulence-related gene diversity present in different Salmonellastrains.
Methods: In this study, thirty-one S. choleraesuis (n = 31), ten Salmonella Typhimurium (n = 10) and eight Salmonella Enteritidis (n = 8) strains were used to detect virulence genes by PCR. Fourteen virulence genes were selected, which have different functions and locations. High carried rate genes in different serovar Salmonellaspp. were evaluated using DGGE assay.
Results: The results showed that most S. choleraesuis strains (93.75%) did not carry sopE1 gene, and most Salmonella Typhimurium strains did not have sopE1, siiD, spvC and gipA genes. All Salmonella Enteritidis strains (100%) did not carry gipA gene, and most of them did not have fljB, siiD, spvC and flgK genes. Different serovar have different virulence gene profiles. In this study, high carried rate genes in different serovar Salmonella spp., such as sopB, spvC, mgtC and ssaQ genes, were evaluated using DGGE assay. The results showed that sopB, spvC and mgtC genes have no different from three serovar Salmonella strains by DGGE, except ssaQgene.
Significance: In this study, DGGE method was used as a rapidly screening method to search for mutations in virulence genes of infectious Salmonella spp. It may facilitate epidemiologic studies with other Salmonella or related foodborne bacteria and could serve as an appropriate alternative sub-typing method.